Some communications protocols may use adaptive modulation (also known as adaptive bit loading), wherein the modulation type can vary by subcarrier. This may occur, for example, with respect to communications using the sub-carriers in various orthogonal frequency-division multiplexing (OFDM) systems. Thus, when adaptively modulated data, which may include packets, is sent to a receiver, a question may arise: Should the modulation used in conjunction with the communication be indicated as well (e.g., should the data be self-defined), or should the data be sent without indicating the modulation type (e.g., should the data be non-self-defined)? Transmitting self-defined data may incur greater on-air overhead. On the other hand, sending non-self-defined data may require several assumptions about the receiver state.